void * worker_loop(void * arg_void) {
WorkerLoopArgs * arg = arg_void;
StateMachine * stateMachine;
DfaSet * dfaSet = arg->dfaSet;
state_machine_id machine_id = arg->machine_id;
readlock(dfaSet->lock, machine_id);
DEBUG("Worker loop: %ld\n", machine_id);
stateMachine = getSmash(dfaSet->smash, machine_id);
assert(stateMachine->machine_id == machine_id);
if(pthread_detach(stateMachine->worker_thread) != 0) {
perror("pthread_detach");
}
readunlock(dfaSet->lock);
inner_worker_loop(arg_void);
writelock(dfaSet->lock, machine_id);
DEBUG("Freeing machine %ld\n", machine_id);
freeSmash(dfaSet->smash, machine_id);
writeunlock(dfaSet->lock);
return 0;
}
static void stasis_alloc_register_old_regions(stasis_alloc_t* alloc) {
pageid_t boundary = REGION_FIRST_TAG;
boundary_tag t;
DEBUG("registering old regions\n");
int succ = TregionReadBoundaryTag(-1, boundary, &t);
if(succ) {
do {
DEBUG("boundary tag %lld type %d\n", boundary, t.allocation_manager);
if(t.allocation_manager == STORAGE_MANAGER_TALLOC) {
for(pageid_t i = 0; i < t.size; i++) {
Page * p = loadPage(-1, boundary + i);
readlock(p->rwlatch,0);
if(p->pageType == SLOTTED_PAGE) {
stasis_allocation_policy_register_new_page(alloc->allocPolicy, p->id, stasis_record_freespace(-1, p));
DEBUG("registered page %lld\n", boundary+i);
} else {
abort();
}
unlock(p->rwlatch);
releasePage(p);
}
}
} while(TregionNextBoundaryTag(-1, &boundary, &t, 0)); //STORAGE_MANAGER_TALLOC)) {
}
}
int TrecordType(int xid, recordid rid) {
Page * p;
p = loadPage(xid, rid.page);
readlock(p->rwlatch,0);
int ret;
ret = stasis_record_type_read(xid, p, rid);
unlock(p->rwlatch);
releasePage(p);
return ret;
}
void *reader (void *args)
{
rwargs *a = static_cast<rwargs *>(args);
int d;
do
{
readlock (a->lock, a->id);
d = data;
usleep (a->delay);
readunlock (a->lock);
RPMS_DEBUG( LOGNAME, "Reader" + rpms::convert<std::string>(a->id) + ": data = " + rpms::convert<std::string>(d) );
usleep (a->delay);
} while (d != 0);
RPMS_DEBUG( LOGNAME, "Reader" + rpms::convert<std::string>(a->id) + ": finished" );
return 0;
}
int TrecordSize(int xid, recordid rid) {
int ret;
Page * p;
p = loadPage(xid, rid.page);
readlock(p->rwlatch,0);
rid.size = stasis_record_length_read(xid, p, rid);
if(stasis_record_type_read(xid,p,rid) == BLOB_SLOT) {
blob_record_t r;
stasis_record_read(xid,p,rid,(byte*)&r);
ret = r.size;
} else {
ret = rid.size;
}
unlock(p->rwlatch);
releasePage(p);
return ret;
}
void * run_request(DfaSet * dfaSet, state_machine_id machine_id) {
void * ret;
WorkerLoopArgs * worker_loop_args = malloc(sizeof(WorkerLoopArgs));
StateMachine * machine;
readlock(dfaSet->lock, 600);
machine = getSmash(dfaSet->smash, machine_id);
worker_loop_args->dfaSet = dfaSet;
worker_loop_args->machine_id = machine_id;
machine->worker_thread = pthread_self();
readunlock(dfaSet->lock);
ret = inner_worker_loop(worker_loop_args);
return (void*)ret;
}
static void stasis_alloc_reserve_new_region(stasis_alloc_t* alloc, int xid) {
void* nta = TbeginNestedTopAction(xid, OPERATION_NOOP, 0,0);
pageid_t firstPage = TregionAlloc(xid, TALLOC_REGION_SIZE, STORAGE_MANAGER_TALLOC);
int initialFreespace = -1;
for(pageid_t i = 0; i < TALLOC_REGION_SIZE; i++) {
TinitializeSlottedPage(xid, firstPage + i);
if(initialFreespace == -1) {
Page * p = loadPage(xid, firstPage);
readlock(p->rwlatch,0);
initialFreespace = stasis_record_freespace(xid, p);
unlock(p->rwlatch);
releasePage(p);
}
stasis_allocation_policy_register_new_page(alloc->allocPolicy, firstPage + i, initialFreespace);
}
TendNestedTopAction(xid, nta);
}
static const LogEntry * stasis_log_impl_in_memory_read_entry(stasis_log_t* log,
lsn_t lsn) {
stasis_log_impl_in_memory * impl = log->impl;
DEBUG("lsn: %ld\n", lsn);
readlock(impl->globalOffset_lock, 0);
if(lsn >= impl->nextAvailableLSN) {
unlock(impl->globalOffset_lock);
return NULL;
}
if(!(lsn-impl->globalOffset >= 0 && lsn-impl->globalOffset< impl->bufferLen)) {
unlock(impl->globalOffset_lock);
return NULL;
}
LogEntry * ptr = impl->buffer[lsn - impl->globalOffset];
unlock(impl->globalOffset_lock);
assert(ptr);
assert(ptr->LSN == lsn);
DEBUG("lsn: %ld prevlsn: %ld\n", ptr->LSN, ptr->prevLSN);
return ptr;
}
dataTuple* dataPage::iterator::getnext() {
len_t len;
bool succ;
if(dp == NULL) {
return NULL;
}
// XXX hack: read latch the page that the record will live on.
// This should be handled by a read_data_in_latch function, or something...
Page * p = loadPage(dp->xid_, dp->calc_chunk_from_offset(read_offset_).page);
readlock(p->rwlatch, 0);
succ = dp->read_data((byte*)&len, read_offset_, sizeof(len));
if((!succ) || (len == 0)) {
unlock(p->rwlatch);
releasePage(p);
return NULL;
}
read_offset_ += sizeof(len);
byte * buf = (byte*)malloc(len);
succ = dp->read_data(buf, read_offset_, len);
// release hacky latch
unlock(p->rwlatch);
releasePage(p);
if(!succ) {
read_offset_ -= sizeof(len);
free(buf);
return NULL;
}
read_offset_ += len;
dataTuple *ret = dataTuple::from_bytes(buf);
free(buf);
return ret;
}
void * inner_worker_loop(void * arg_void) {
WorkerLoopArgs * arg = arg_void;
DfaSet * dfaSet = arg->dfaSet;
const state_machine_id machine_id = arg->machine_id;
int timeout = 0; /* Run through the loop immediately the first time around. */
int state = 0;
int first = 1;
StateMachine* stateMachine;
free(arg_void);
readlock(dfaSet->lock, machine_id);
stateMachine = getSmash(dfaSet->smash, machine_id);
pthread_mutex_lock(stateMachine->mutex);
while(1) {
int rc = 0;
state_name i, state_idx = NULL_STATE;
/** @todo inner worker loop doesn't seem to 'do the right thing' with respect to timing */
if(1|| !stateMachine->pending) { /* If no pending messages, go to sleep */
struct timeval now;
struct timespec timeout_spec;
pthread_cond_t * cond;
pthread_mutex_t * mutex;
long usec;
cond = stateMachine->sleepCond;
mutex = stateMachine->mutex;
readunlock(dfaSet->lock);
/* A note on locking: This loop maintains a read lock everywhere
except for this call to sleep, and upon termination when it
requires a write lock. */
gettimeofday(&now, NULL);
usec = now.tv_usec + timeout;
if(usec > 1000000) {
now.tv_sec++;
usec-=1000000;
}
timeout_spec.tv_sec = now.tv_sec;
timeout_spec.tv_nsec = 1000 * usec;
rc = pthread_cond_timedwait (cond, mutex, &timeout_spec );
if(rc == EINVAL) {
perror("pthread");
}
readlock(dfaSet->lock, machine_id);
/* Some other thread may have invalidated our pointer while we
were sleeping witout a lock... no longer true, *but* since
our pointer is local to this thread, we still need to re-read
from the store.*/
assert(stateMachine == getSmash(dfaSet->smash, machine_id));
}
DEBUG("Current State: %d, %d\n", stateMachine->current_state, NULL_STATE_TOMBSTONE);
if(stateMachine->current_state == NULL_STATE_TOMBSTONE) {
DEBUG("Freeing statemachine\n");
break;
}
if(state != stateMachine->current_state) { first = 1; }
state = stateMachine->current_state;
stateMachine->message.type = stateMachine->current_state;
timeout = 690000 +(int) (300000.0*rand()/(RAND_MAX+1.0));
for(i = 0; i < dfaSet->state_count; i++) {
if(dfaSet->states[i].name == stateMachine->current_state) {
state_idx = i;
}
}
assert(state_idx != NULL_STATE);
DEBUG("Worker loop for state machine: %ld still active\n", machine_id);
int send = 1;
if(dfaSet->states[state_idx].retry_fcn != NULL) {
send = dfaSet->states[state_idx].retry_fcn(dfaSet, stateMachine, &(stateMachine->message), stateMachine->message_recipient);
}
if(send) {
if(first) {
first = 0;
} else {
printf("Resending message. Machine # %ld State # %d\n", stateMachine->machine_id, stateMachine->current_state);
}
send_message(&(dfaSet->networkSetup), &(stateMachine->message), stateMachine->message_recipient);
}
}
setSmash(dfaSet->smash, stateMachine->machine_id);
pthread_mutex_unlock(stateMachine->mutex);
readunlock(dfaSet->lock);
return 0;
}
void Tdealloc(int xid, recordid rid) {
stasis_alloc_t* alloc = stasis_runtime_alloc_state();
// @todo this needs to garbage collect empty storage regions.
pthread_mutex_lock(&alloc->mut);
Page * p = loadPage(xid, rid.page);
readlock(p->rwlatch,0);
recordid newrid = stasis_record_dereference(xid, p, rid);
stasis_allocation_policy_dealloced_from_page(alloc->allocPolicy, xid, newrid.page);
int64_t size = stasis_record_length_read(xid,p,rid);
int64_t type = stasis_record_type_read(xid,p,rid);
if(type == NORMAL_SLOT) { type = size; }
byte * preimage = malloc(sizeof(alloc_arg)+size);
((alloc_arg*)preimage)->slot = rid.slot;
((alloc_arg*)preimage)->type = type;
// stasis_record_read() wants rid to have its raw size to prevent
// code that doesn't know about record types from introducing memory
// bugs.
rid.size = size;
stasis_record_read(xid, p, rid, preimage+sizeof(alloc_arg));
// restore rid to valid state.
rid.size = type;
// Ok to release latch; page is still pinned (so no WAL problems).
// allocationPolicy protects us from running out of space due to concurrent
// xacts.
// Also, there can be no reordering of allocations / deallocations ,
// since we're holding alloc->mutex. However, we might reorder a Tset()
// to and a Tdealloc() or Talloc() on the same page. If this happens,
// it's an unsafe race in the application, and not technically our problem.
// @todo Tupdate forces allocation to release a latch, leading to potentially nasty application bugs. Perhaps this is the wrong API!
// @todo application-level allocation races can lead to unrecoverable logs.
unlock(p->rwlatch);
Tupdate(xid, rid.page, preimage,
sizeof(alloc_arg)+size, OPERATION_DEALLOC);
releasePage(p);
pthread_mutex_unlock(&alloc->mut);
if(type==BLOB_SLOT) {
stasis_blob_dealloc(xid,(blob_record_t*)(preimage+sizeof(alloc_arg)));
}
free(preimage);
stasis_transaction_table_set_argument(alloc->xact_table, xid, alloc->callback_id,
AT_COMMIT, alloc);
}
